This invention relates to an ink jet printing head, particularly to eliminate the problem of ink blockage in thermal ink jet type printing machines.
Conventional type printing machines may be of the impact type or the non-impact type, wherein the non-impact type may be an electronic photograph system, an electro-static system, a thermal system or an ink jet system. However, in regard to these systems, the ink jet system is very silent, is of low power consumption and of small physical size; however, a broad use of said ink jet systems has not been realised. A main reason of the non use of ink jet systems is based on the problem of ink jet nozzle blockage. Therefore, the composition of the ink and the nozzle shape have been deeply researched and developed, but have not been sufficient to make the use of ink jet systems free of this problem, thus sufficient reliability is not obtained.
U.S. Pat. No. 4,608,577 discloses a new type of ink jet printer using a film having a plurality of holes or recesses through which the ink passes. However, it is very difficult to densely print by a plurality of holes in the film, since the film is floated by the bubble pressure when the ink is jetted by the heat of the thermal head over a short span of time. Resulting in not obtained the print in a sufficient density. Further, other prior art know to the Applicant include U.S. Pat. Nos: 3,747,120; 4,263,601; 4,308,547; 4,312,009; 4,337,467; 4,366,487; and, 4,515,487.